Recent advances in the area of cell biology and in clinical technique make it possible to think in terms of regeneration of periodontal supporting structure lost to disease. Progenitor cells harbored within remaining health periodontal ligament (PDL) are likely to be cells responsible for mediating such regeneration. The intent of the proposed research is to harvest canine PDL cells using an innovative method of membrane implants, and to compare this method of obtaining PDL cells with the established technique of root scraping. Cells obtained by both techniques will be characterized according to cell types isolated, protein and collagen production and proliferation rate in vitro. The proposed technique, using membrane implants, is thought to have distinct and important advantages. The PDL cells harvested in this manner represent cell populations that have migrated into the wounded area of the PDL and are likely to be highly active. These are precisely the cells of interest in periodontal regeneration. Successful completion of the proposed research should permit us to expand this project into a comprehensive in vitro model for the study of periodontal regeneration.